From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by ug-out-1314.google.com with SMTP id c2so570824ugf for ; Wed, 25 Jul 2007 23:23:03 -0700 (PDT) Message-ID: <7e0bae390707252323k2552c701x5673c55ff2cf119e@mail.gmail.com> Date: Thu, 26 Jul 2007 13:23:03 +0700 From: "Andika Triwidada" Subject: Re: updatedb In-Reply-To: <46A81C39.4050009@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <367a23780707250830i20a04a60n690e8da5630d39a9@mail.gmail.com> <46A773EA.5030103@gmail.com> <46A81C39.4050009@gmail.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Rene Herman Cc: Robert Deaton , linux-kernel@vger.kernel.org, ck list , linux-mm@kvack.org List-ID: On 7/26/07, Rene Herman wrote: > On 07/25/2007 07:15 PM, Robert Deaton wrote: > > > On 7/25/07, Rene Herman wrote: > > >> And there we go again -- off into blabber-land. Why does swap-prefetch > >> help updatedb? Or doesn't it? And if it doesn't, why should anyone > >> trust anything else someone who said it does says? > > > I don't think anyone has ever argued that swap-prefetch directly helps > > the performance of updatedb in any way > > People have argued (claimed, rather) that swap-prefetch helps their system > after updatedb has run -- you are doing so now. > > > however, I do recall people mentioning that updatedb, being a ram > > intensive task, will often cause things to be swapped out while it runs > > on say a nightly cronjob. > > Problem spot no. 1. > > RAM intensive? If I run updatedb here, it never grows itself beyond 2M. Yes, > two. I'm certainly willing to accept that me and my systems are possibly not > the reference but assuming I'm _very_ special hasn't done much for me either > in the past. Might be insignificant, but updatedb calls find (~2M) and sort (~26M). Definitely not RAM intensive though (RAM is 1GB). > > The thing updatedb does do, or at least has the potential to do, is fill > memory with cached inodes/dentries but Linux does not swap to make room for > caches. So why will updatedb "often cause things to be swapped out"? > [ snip ] -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org